How did the Habsburg marriage agreements of 1515 strengthen claims to Bohemia and Hungary?

The Habsburg marriage agreements of 1515 were a strategic diplomatic maneuver by Maximilian I to secure dynastic influence in Central Europe. By arranging a double marriage between his family and the Jagiellon line—which then ruled both Bohemia and Hungary—Maximilian successfully revived long-standing Habsburg succession claims to these kingdoms.12

These agreements became critical following the untimely death of the Jagiellon king Louis II at the Battle of Mohács in 1526. Because Ferdinand I had married Louis II’s sister, Anna, in 1521, the 1515 treaties provided the legal and political foundation for Ferdinand to assert his right to the vacant thrones. Consequently, the union of Austria, Bohemia, and Hungary emerged as a central pillar of Habsburg policy, allowing Ferdinand to be elected king of Bohemia and to pursue his claim to the Hungarian crown.3456